A Discharging Treatment Method and System for Recycling Waste Lithium Batteries

Abstract

The present invention discloses a discharge treatment method and system for recycling waste lithium batteries, which relates to the technical field of lithium battery recycling. The steps of the method include: collecting the battery voltage and current through an integrated sensor and a microprocessor, and intelligently adjusting the discharge speed through a discharge speed adjustment strategy; immersing the physically discharged battery into an electrolyte solution, and adjusting the flow rate of the electrolyte and the solution temperature by real-time monitoring of the gas generated during the discharge process; obtaining the actual discharge voltage of the battery through the flow rate of the electrolyte and the solution temperature, and adjusting the flow rate of the electrolyte and the solution temperature again through the actual discharge voltage of the battery and the maximum discharge current; when it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold, the system automatically cuts off the power supply. The present invention realizes intelligent adjustment of the discharge speed, adjusts the control parameters according to the real-time voltage error, and improves the stability and safety of the discharge process.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery recycling, and specifically provides a discharge treatment method and system for recycling waste lithium batteries. Background Art

[0002] With the popularization of electronic products such as electric vehicles and smart phones, lithium batteries, as their core energy components, have seen a year-on-year increase in market demand. However, with the increase in the usage of lithium batteries, the problem of recycling waste lithium batteries has gradually emerged. If waste lithium batteries are not properly treated, it will not only cause a great waste of resources, but also may cause serious environmental pollution. Therefore, the recycling of waste lithium batteries has become an important problem that needs to be solved urgently.

[0003] One of the core links in the recycling of waste lithium batteries is discharge treatment. Discharge treatment is the first step to ensure the safe recycling of lithium batteries. It aims to safely release the energy inside the battery by controlling the discharge process, providing a safe premise for subsequent disassembly, separation, and reuse. However, traditional discharge methods have many problems, such as slow discharge speed, low discharge efficiency, and complex operation, making it difficult to meet the current requirements for the recycling of waste lithium batteries.

[0004] For example, the Chinese patent with the publication number CN116706302A discloses a lithium battery recycling method. In the pretreatment process, lithium battery monomers are first detected and decomposed, then the lithium battery monomers are crushed, dried, and sorted. Then, lithium iron phosphate battery powder and ternary battery powder are obtained through pyrolysis. Next, the lithium iron phosphate battery powder and ternary battery powder are respectively mixed into sulfuric acid, and finally, water-soluble lithium sulfate is obtained through roasting; in the positive electrode material repair process, waste lithium iron phosphate positive electrode sheets and scraps are shredded, pyrolyzed, screened, iron-removed, pulverized, and magnetically iron-removed, and then mixed and packaged; in the acid dissolution and impurity removal process, it includes impurity removal of lithium iron phosphate batteries and impurity removal of ternary batteries. The impurity removal of lithium iron phosphate batteries removes copper, fluorine, and aluminum, and the impurity removal of ternary batteries removes nickel, cobalt, manganese, copper, aluminum, and iron; in the extraction process, it includes extraction and impurity removal and extraction of manganese, nickel, cobalt, and magnesium; lithium hydroxide is prepared.

[0005] However, this design involves multiple chemical and physical reactions throughout the recycling process, and sparks or static electricity may be generated during the crushing process, which is extremely dangerous in an environment containing combustible substances. Therefore, safety issues are not considered. For this reason, the present invention provides a discharge treatment method and system for recycling waste lithium batteries. Summary of the Invention

[0006] The purpose of the present invention is to provide a discharge treatment method and system for recycling waste lithium batteries to solve the existing problems mentioned in the above background art.

[0007] To achieve the above object, the present invention provides the following technical solution: A discharge treatment method for recycling waste lithium batteries, comprising the following steps:

[0008] S1. By integrating sensors and a microprocessor, collect the battery voltage and current, and intelligently adjust the discharge rate through a discharge rate adjustment strategy;

[0009] S2. Immerse the physically discharged battery in an electrolyte solution, and adjust the flow rate of the electrolyte and the solution temperature by monitoring the gas generated during the discharge process in real time;

[0010] S3. Obtain the actual discharge voltage of the battery from the flow rate of the electrolyte and the solution temperature, and adjust the flow rate of the electrolyte and the solution temperature again through the actual discharge voltage of the battery and the maximum discharge current;

[0011] S4. When it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold, the system automatically cuts off the power supply.

[0012] The further improvement of the present invention lies in that the discharge rate adjustment strategy is implemented through a discharge rate PID controller, and the specific steps include:

[0013] S11. Connect the battery to the short - circuit circuit built in the system, and the microprocessor reads the battery voltage through an analog - to - digital converter, and calculates the maximum discharge current of the battery \(I_{max}=V_{max} / R_{min}\), where \(V_{max}\) represents the maximum voltage of the battery and \(R_{min}\) is the minimum resistance of the short - circuit circuit;

[0014] S12. Define the desired discharge time \(t\) target , and calculate the target discharge current \(I\) target \(=C / t\) target ;

[0015] S13. Monitor the current discharge current in real time to obtain the current discharge current \(I\) current , when the current discharge current is less than the maximum discharge current of the battery, calculate the discharge current difference value \(e(t)=I\) target \(-I\) current , when the current discharge current is greater than or equal to the maximum discharge current of the battery, issue an alarm;

[0016] S14. Calculate the output of the discharge rate PID controller where, \(K\) p represents the proportional coefficient, \(K\) i represents the integral coefficient, \(K\) d represents the differential coefficient;

[0017] S15. Adjust the minimum resistance of the discharge circuit in step S11 according to the output of the discharge speed PID controller;

[0018] S16. Real-time monitor the battery voltage through the microprocessor, set the termination voltage threshold, and end the discharge when the current battery voltage is less than the termination voltage threshold.

[0019] The further improvement of the present invention lies in that the specific steps of S2 include:

[0020] S21. Real-time monitor the gas concentration gac through a sensor ret ;

[0021] S22. Set the gas concentration threshold Tgac and the sliding mode surface S, and define the sliding mode surface S = gac ret -Tgac;

[0022] S23. Apply the equivalent control rate to maintain the system state on the sliding mode surface. The calculation formula for the equivalent control rate of the electrolyte flow velocity is u eq,F =k F (Tgac - gac ret ), and the calculation formula for the equivalent control rate of the solution temperature is u eq,T =k T (Tgac - gac ret ), where k F and k T represent the equivalent controller gains;

[0023] S24. Make the system state quickly approach the sliding mode surface by switching the control law. The switching control rate of the electrolyte flow velocity is u sw,F =-k sw,F ×sign(gac ret -Tgac), and the switching control rate of the solution temperature is u sw,T =-k sw，T ×sign(gac ret -Tgac), where k sw，F and k sw，T represent the switching controller gains;

[0024] S25. Calculate the output of the sliding mode controller through the equivalent control rate and the switching control rate to adjust the electrolyte flow velocity ΔF and the solution temperature ΔT. The controller output is expressed as: where u eq，F represents the equivalent control part of the electrolyte flow velocity, u eq，T represents the equivalent control part of the solution temperature, u sw，F represents the switching control part of the electrolyte flow velocity, u sw，F represents the switching control part of the solution temperature;

[0025] S26. Adjust the electrolyte flow rate ΔF and the solution temperature ΔT in real time until the sliding mode surface S ≤ 0.

[0026] A further improvement of the present invention lies in that the specific steps of S3 include:

[0027] S31. Calculate the actual discharge voltage V of the battery according to the electrolyte flow rate ΔF and the solution temperature ΔT discharge = Vocv - I × R ohmic - α1 × ΔF - α2 × ΔT, where Vocv represents the open-circuit voltage of the battery, I represents the working current of the battery, and R ohmic represents the minimum resistance of the discharge circuit obtained in step S15, α1 represents the weight of the electrolyte flow rate, and α2 represents the weight of the solution temperature;

[0028] S32. Calculate the predicted value I of the actual discharge current discharge = V discharge / R ohmic and the maximum voltage threshold V th = R ohmic × I_max;

[0029] S33. Through the voltage feedback control strategy, adjust the electrolyte flow rate and the solution temperature again.

[0030] A further improvement of the present invention lies in that the voltage feedback control strategy is implemented by a voltage feedback PID controller, and the specific steps include:

[0031] S331. Calculate the voltage error e(v) = R ohmic × I_max - V discharge ;

[0032] S332. Update the integral term I(v) of the voltage feedback PID controller, I(v) = I(v) + (R ohmic × I_max - V discharge )Δt, where Δt represents the integral, and the differential term D(v) = e(v) - e(v) prev / Δt, where e(v) prev represents the voltage error at the previous moment;

[0033] S333. Calculate the output u(v) of the voltage feedback PID controller, u(v) = K p (v) × e(v) + K i (v) × I(v) + K d (v) × D(v), where K p (v) represents the proportional coefficient of the voltage feedback PID controller, and K i (v) represents the integral coefficient of the voltage feedback PID controller, Kd (v) represents the differential coefficient of the voltage feedback PID controller;

[0034] S334. Update the electrolyte flow rate F = F + (β × u(v)), where β is an adjustment factor;

[0035] S335. Update the solution temperature T = T + (χ × u(v)), where χ is another adjustment factor;

[0036] S336. When the actual output voltage V discharge > V th , after forcibly reducing the solution temperature to the set minimum temperature value, update the error at the previous moment;

[0037] S337. Repeat steps S331 - S336 until V discharge ≤V th and gac ret ≤Tgac.

[0038] On the other hand, the present invention provides a discharge treatment system for recycling waste lithium batteries, including:

[0039] A physical short - circuit discharge module, which is used to collect the battery voltage and current by integrating sensors and microprocessors, and intelligently adjust the discharge rate through a discharge rate adjustment strategy;

[0040] A chemical discharge module, which is used to immerse the battery that has undergone physical discharge into an electrolyte solution and dynamically adjust the flow rate of the electrolyte and the solution temperature;

[0041] A response stop module, which is used to automatically cut off the power supply of the system when it detects that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold.

[0042] The further improvement of the present invention lies in that the chemical discharge module includes a gas - electrolyte control unit and a voltage - electrolyte control unit; the gas - electrolyte control unit is used to adjust the flow rate of the electrolyte and the solution temperature by real - time monitoring of the gas generated during the discharge process; the voltage - electrolyte control unit is used to obtain the actual discharge voltage of the battery from the flow rate of the electrolyte and the solution temperature obtained by the gas - electrolyte control unit, and then adjust the flow rate of the electrolyte and the solution temperature again through the actual discharge voltage of the battery and the maximum discharge current.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] 1. By monitoring key parameters such as gas generation, electrolyte flow rate, and solution temperature in real time, the present invention intelligently adjusts the discharge rate. The system combines physical short-circuit discharge and chemical discharge to achieve efficient and safe treatment of waste lithium batteries. Among them, the sliding mode controller ensures the rapid stability of the system state, while the voltage feedback PID controller adjusts the control parameters according to the real-time voltage error, further improving the stability and safety of the discharge process;

[0045] 2. Through the chemical discharge module and the response stop module, which are further refined into gas-electrolyte control and voltage-electrolyte control, more precise discharge control is achieved. This not only improves the recycling efficiency of waste lithium batteries but also significantly enhances the safety and efficiency of the treatment process through automation and intelligent means, providing a new solution for the recycling and utilization of waste lithium batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a flowchart of a discharge treatment method for recycling waste lithium batteries according to the present invention;

[0047] Figure 2 It shows a flowchart of the discharge rate PID controller of a discharge treatment method for recycling waste lithium batteries according to the present invention;

[0048] Figure 3 It shows a flowchart of the voltage feedback PID controller of a discharge treatment method for recycling waste lithium batteries according to the present invention;

[0049] Figure 4 It is a framework diagram of a discharge treatment system for recycling waste lithium batteries according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] The technical solution of the present invention will be described in detail below with reference to the drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. Without conflict, the technical features in the embodiments of the present invention and the embodiments can be combined with each other.

[0051] The term "and / or" merely describes the associated relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " generally represents an "or" relationship between the associated objects before and after.

[0052] Embodiment 1

[0053] Figure 1 It shows a flowchart of a discharge treatment method for recycling waste lithium batteries disclosed in this embodiment. The steps are as follows:

[0054] S1. By integrating a sensor and a microprocessor, the battery voltage and current are collected, and the discharge speed is intelligently adjusted through a discharge speed regulation strategy.

[0055] The discharge speed regulation strategy is implemented through a discharge speed PID controller. Figure 2 The flowchart of the discharge speed PID controller for a discharge treatment method of recycling waste lithium batteries according to the present invention is shown. The specific steps include:

[0056] S11. Connect the battery to the short - circuit circuit built into the system. The microprocessor reads the battery voltage through an analog - to - digital converter and calculates the maximum discharge current of the battery \(I_{max}=V_{max} / R_{min}\), where \(V_{max}\) represents the maximum voltage of the battery and \(R_{min}\) is the minimum resistance of the short - circuit circuit.

[0057] S12. Define the desired discharge time \(t\) target , and based on the battery capacity \(C\) and the desired discharge time, calculate the target discharge current \(I\) target \(=C / t\) target ;

[0058] S13. Monitor the current discharge current in real - time to obtain the current discharge current \(I\) current . When the current discharge current is less than the maximum discharge current of the battery, calculate the discharge current difference value \(e(t)=I\) target \(-I\) current . When the current discharge current is greater than or equal to the maximum discharge current of the battery, an alarm is issued.

[0059] S14. Calculate the output of the discharge speed PID controller where \(K\) p represents the proportional coefficient, \(K\) i represents the integral coefficient, and \(K\) d represents the differential coefficient;

[0060] S15. Adjust the minimum resistance of the discharge circuit in step S11 according to the output of the discharge speed PID controller.

[0061] S16. Monitor the battery voltage in real - time through the microprocessor, set the termination voltage threshold. When the current battery voltage is less than the termination voltage threshold, the discharge ends.

[0062] S2. Immerse the battery that has undergone physical discharge into the electrolyte solution, and adjust the flow rate of the electrolyte and the solution temperature by monitoring the gas generated during the discharge process in real - time.

[0063] The specific steps of S2 include:

[0064] S21. Monitor the gas concentration \(g_{ac}\) in real - time through a sensor ret ;

[0065] S22. Set the gas concentration threshold Tgac and the sliding mode surface S, and define the sliding mode surface S = gac ret -Tgac;

[0066] S23. Use the equivalent control rate to maintain the system state on the sliding mode surface. Then, the calculation formula for the equivalent control rate of the electrolyte flow velocity is u eq,F = k F (Tgac - gac ret ), and the calculation formula for the equivalent control rate of the solution temperature is u eq,T = k T (Tgac - gac ret ), where k F and k T represent the equivalent controller gains;

[0067] S24. Make the system state quickly approach the sliding mode surface by switching the control law. Then, the switching control rate of the electrolyte flow velocity u sw,F = -k sw,F × sign(gac ret - Tgac), and the switching control rate of the solution temperature u sw,T = -k sw，T × sign(gac ret - Tgac), where k sw，F and k sw，T represent the switching controller gains;

[0068] S25. Calculate the output of the sliding mode controller through the equivalent control rate and the switching control rate to adjust the electrolyte flow velocity ΔF and the solution temperature ΔT. The controller output is expressed as: where u eq，F represents the equivalent control part of the electrolyte flow velocity, u eq，T represents the equivalent control part of the solution temperature, u sw，F represents the switching control part of the electrolyte flow velocity, u sw，F represents the switching control part of the solution temperature;

[0069] S26. Adjust the electrolyte flow velocity ΔF and the solution temperature ΔT in real time until the sliding mode surface S ≤ 0.

[0070] S3. Obtain the actual discharge voltage of the battery through the electrolyte flow velocity and the solution temperature, and adjust the electrolyte flow velocity and the solution temperature again through the actual discharge voltage of the battery and the maximum discharge current;

[0071] The specific steps of S3 include:

[0072] S31. Calculate the actual discharge voltage V of the battery based on the electrolyte flow rate ΔF and the solution temperature ΔT discharge = Vocv - I × R ohmic - α1 × ΔF - α2 × ΔT, where Vocv represents the open-circuit voltage of the battery, I represents the working current of the battery, and R ohmic represents the minimum resistance of the discharge circuit obtained in step S15, α1 represents the weight of the electrolyte flow rate, and α2 represents the weight of the solution temperature;

[0073] S32. Calculate the predicted value I of the actual discharge current discharge = V discharge / R ohmic and the maximum voltage threshold V th = R ohmic × I_max;

[0074] S33. Through the voltage feedback control strategy, adjust the electrolyte flow rate and the solution temperature again.

[0075] The voltage feedback control strategy is implemented by a voltage feedback PID controller, Figure 3 which shows the flowchart of the voltage feedback PID controller for a discharge treatment method of recycling waste lithium batteries according to the present invention. The specific steps include:

[0076] S331. Calculate the voltage error e(v) = R ohmic × I_max - V discharge ;

[0077] S332. Update the integral term I(v) of the voltage feedback PID controller = I(v) + (R ohmic × I_max - V discharge )Δt, where Δt represents integration, and the differential term D(v) = e(v) - e(v) prev / Δt, where e(v) prev represents the voltage error at the previous moment;

[0078] S333. Calculate the output u(v) of the voltage feedback PID controller = K p (v) × e(v) + K i (v) × I(v) + K d (v) × D(v), where K p (v) represents the proportional coefficient of the voltage feedback PID controller, K i (v) represents the integral coefficient of the voltage feedback PID controller, and K d (v) represents the differential coefficient of the voltage feedback PID controller;

[0079] S334. Update the electrolyte flow rate F = F + (β × u(v)), where β is a regulation factor;

[0080] S335. Update the solution temperature T = T + (χ × u(v)), where χ is another regulation factor;

[0081] S336. When the actual output voltage V discharge > V th , force the solution temperature to be reduced to the set minimum temperature value, and then update the error at the previous moment;

[0082] S337. Repeat steps S331 - S336 until V discharge ≤ V th and gac ret ≤ Tgac.

[0083] S4. When it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold, the system automatically cuts off the power supply.

[0084] The setting of the above - mentioned threshold and weight can be set according to the default settings of the present invention or can be set by the operator himself.

[0085] Embodiment 2

[0086] Figure 4 Fig. shows the framework diagram of a discharge treatment system for recycling waste lithium - ion batteries according to the present invention. Based on the same inventive concept as Embodiment 1, the present invention provides a discharge treatment system for recycling waste lithium - ion batteries, including:

[0087] A physical short - circuit discharge module, which is used to collect the battery voltage and current by integrating sensors and a micro - processor, and intelligently adjust the discharge rate through a discharge rate adjustment strategy;

[0088] A chemical discharge module, which is used to immerse the battery that has undergone physical discharge into an electrolyte solution and dynamically adjust the flow rate of the electrolyte and the solution temperature;

[0089] A response stop module, which is used to automatically cut off the power supply when it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold.

[0090] The chemical discharge module includes a gas - electrolyte control unit and a voltage - electrolyte control unit; the gas - electrolyte control unit is used to adjust the flow rate of the electrolyte and the solution temperature by real - time monitoring of the gas generated during the discharge process; the voltage - electrolyte control unit is used to obtain the actual discharge voltage of the battery from the flow rate of the electrolyte and the solution temperature obtained by the gas - electrolyte control unit, and then adjust the flow rate of the electrolyte and the solution temperature again through the actual discharge voltage of the battery and the maximum discharge current.

[0091] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0092] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0093] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including instruction means, and the instruction means realizes the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0094] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide steps for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0095] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the claims of the present invention. These all fall within the protection scope of the present invention.

Claims

1. A discharge treatment method for recycling waste lithium batteries, characterized in that: The following steps are involved: S1, collect battery voltage and current through integrated sensors and microprocessors, and intelligently adjust the discharge speed through the discharge speed adjustment strategy; S2, immersing the physically discharged battery into an electrolyte solution, and adjusting the flow rate of the electrolyte and the solution temperature by real-time monitoring the gas generated during the discharge process; S3, obtaining the actual discharge voltage of the battery according to the flow rate of the electrolyte and the solution temperature, and adjusting the flow rate of the electrolyte and the solution temperature again according to the actual discharge voltage and the maximum discharge current of the battery; S4. When it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold, the system automatically cuts off the power supply; The specific steps of S2 include: S21, real-time monitoring of gas concentration gac through sensors ret ; S22. Set the gas concentration threshold Tgac and the sliding surface S, and define the sliding surface S = gac ret -Tgac; S23. The equivalent control rate is used to maintain the system state on the sliding surface. The calculation formula of the equivalent control rate of the electrolyte flow velocity is u eq,F =k F (Tgac-gac ret ), the calculation formula of the equivalent control rate of solution temperature is u eq,T =k T (Tgac-gac ret ), where k F and k T represents the equivalent controller gain; S24, by switching the control rate, the system state quickly approaches the sliding surface, then the electrolyte flow speed switching control rate u sw,F =-k sw,F ×sign(gac ret -Tgac), solution temperature switching control rate u sw,T =-k sw,T ×sign(gac ret -Tgac), where k sw,F and k sw,T represents the switching controller gain; S25, calculating the output of the sliding mode controller by the equivalent control rate and the switching control rate to adjust the electrolyte flow rate ΔF and the solution temperature ΔT, and the controller output is expressed as: Among them, u eq,F represents the equivalent control part of the electrolyte flow rate, u eq,T represents the equivalent control part of solution temperature, u sw,F represents the electrolyte flow rate switching control part, u sw,F Indicates the solution temperature switching control part; S26, adjusting the electrolyte flow velocity ΔF and the solution temperature ΔT in real time until the sliding surface S≤0.

2. A discharge treatment method for recycling waste lithium batteries according to claim 1, characterized in that: The discharge speed regulation strategy is implemented by a discharge speed PID controller, and the specific steps include: S11, connect the battery to the built-in short-circuit circuit of the system, and the microprocessor reads the battery voltage through the analog-to-digital converter to calculate the maximum discharge current of the battery I_max=V_max / R_min, where V_max represents the maximum voltage of the battery and R_min is the minimum resistance of the short-circuit circuit; S12. Define the expected discharge time t target , based on the battery capacity C and the expected discharge time, calculate the target discharge current I target =C / t target ; S13, real-time monitoring of the current discharge current to obtain the current discharge current I current , when the current discharge current is less than the maximum discharge current of the battery, the discharge current difference value e(t) is calculated as I target -I current , when the current discharge current is greater than or equal to the maximum discharge current of the battery, an alarm is issued; S14, calculate the discharge speed PID controller output Among them, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K d represents the differential coefficient; S15, adjusting the minimum resistance of the discharge circuit in step S11 according to the output of the discharge speed PID controller; S16, monitoring the battery voltage in real time through the microprocessor, setting a termination voltage threshold, and terminating the discharge when the current battery voltage is less than the termination voltage threshold.

3. A discharge treatment method for recycling waste lithium batteries according to claim 2, characterized in that: The specific steps of S3 include: S31, calculating the actual discharge voltage V of the battery according to the electrolyte flow rate ΔF and the solution temperature ΔT discharge =Vocv-I×R ohmic -α1×ΔF-α2×ΔT, where Vocv represents the open circuit voltage of the battery, I represents the operating current of the battery, and R ohmic represents the minimum resistance of the discharge circuit obtained in step S15, α1 represents the weight of the electrolyte flow rate, and α2 represents the weight of the solution temperature; S32, calculate the actual discharge current prediction value I discharge =V discharge / R ohmic and the maximum voltage threshold V th =R ohmic ×I_max; S33. Adjust the flow rate and solution temperature of the electrolyte again through the voltage feedback control strategy.

4. A discharge treatment method for recycling waste lithium batteries according to claim 3, characterized in that: The voltage feedback control strategy is implemented by a voltage feedback PID controller, and the specific steps include: S331, calculate voltage error e(v) = R ohmic ×I_max-V discharge ; S332, update the integral term of the voltage feedback PID controller I(v)=I(v)+(R ohmic ×I_max-V discharge )Δt, where Δt represents the integral, and the differential term D(v) = e(v)-e(v)prev / Δt, where e(v)prev represents the voltage error at the previous moment; S333, calculating the output u(v) of the voltage feedback PID controller = K p (v)×e(v)+K i (v)×I(v)+K d (v)×D(v), where K p (v) represents the proportional coefficient of the voltage feedback PID controller, K i (v) represents the integral coefficient of the voltage feedback PID controller, K d (v) represents the differential coefficient of the voltage feedback PID controller; S334, updating the electrolyte flow rate F = F + (β × u (v)), β is a regulating factor; S335, updating the solution temperature T = T + (χ × u (v)), χ is another adjustment factor; S337, repeat steps S331-S336 until V is satisfied discharge ≤V th And gac ret ≤Tgac.

5. A discharge treatment system for recycling waste lithium batteries, used to perform a discharge treatment method for recycling waste lithium batteries as claimed in any one of claims 1 to 4, characterized in that: include: The physical short-circuit discharge module is used to collect battery voltage and current through integrated sensors and microprocessors, and intelligently adjust the discharge speed through the discharge speed adjustment strategy; A chemical discharge module is used to immerse the physically discharged battery into an electrolyte solution and dynamically adjust the flow rate of the electrolyte and the solution temperature; The response stop module is used to automatically cut off the power supply of the system when it is detected that the battery voltage is lower than the discharge termination threshold or the solution temperature is greater than the set solution temperature threshold.

6. A discharge treatment system for recycling waste lithium batteries according to claim 5, characterized in that: The chemical discharge module includes a gas-electrolyte control unit and a voltage-electrolyte control unit; the gas-electrolyte control unit is used to adjust the flow rate and solution temperature of the electrolyte by real-time monitoring the gas generated during the discharge process; the voltage-electrolyte control unit is used to obtain the actual discharge voltage of the battery by the flow rate and solution temperature of the electrolyte obtained by the gas-electrolyte control unit, and adjust the flow rate and solution temperature of the electrolyte again according to the actual discharge voltage and maximum discharge current of the battery.

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